Latest Reports The Front Lines of Japanese Excavations in 2020!

Paleolithic Period  (Morisaki Kazuki)

The culture of hunter-gatherers, rich in regional flavor

At the Nishi Tomioka/Nagatake Site in Isehara City, Kanagawa Prefecture, a group of stone tools indicating the lively manufacture of projectile points and microblades that developed around the end of the Upper Paleolithic has been discovered. The projectile points are spearpoints that have been carefully processed into a laurel-leaf shape, and the microblades are razor blade-like stone tools that were hafted into bone or wooden shafts to make spears or knives. At the base of Mount Ōyama, well known also as a tourist location, an image emerges of people following a hunting way of life while producing a variety of tools in specialized fashion.

The Takami I Site in Iyo City, Ehime Prefecture, was excavated in 2017 and the results published in 2019. On the Shikoku side of the western Inland Sea region, Paleolithic sites are small in scale and not numerous, but at this site several thousand stone tools were recovered along with stone scatters that were cooking facilities, making this an important discovery. The stone tools include types well known in Kyushu and the Kinki region, and it is possible that the people who occupied this site had a culture influenced by those regions.


The Preservation of Paleolithic sites advances

In recent years the preservation of sites from the Paleolithic to the Incipient phase of the Jōmon periods has been advancing. The Sumi Furusawa Site in Shisui Town, Chiba Prefecture, is a large-scale circular settlement made around the start of the Upper Paleolithic period (approximately 40,000–15,000 years ago). Among the large number of circular settlements known, as this is the only one for which the entire scale is clear and which has been preserved in its present condition, in 2019 it was designated a Historic Site. Also receiving the designation of Historic Site, the Shiraho Saonetabaru Cave Ruins in Ishigaki City, Okinawa Prefecture, is a cemetery from approximately 30,000–20,000 years ago where the custom of leaving the dead exposed by placing them next to the wall of a limestone cave was practiced. It is the first discovery of such a site, containing numerous human bones and also relating unique funerary customs.


Jōmon Period  (Saitō Yasushi)

New knowledge of lacquer culture of the southern Tōhoku region

Excavation has been conducted at the Maeda Site in Kawamata Town, Fukushima Prefecture, from the 2018 fiscal year in conjunction with construction for the improvement of a national road. In the 2018 fiscal year a group of storage pits from the Final Jōmon period (approximately 2,800 years ago) and a water course from the end of the Middle Jōmon (approximately 4,100 years ago) were discovered, and in the 2019 fiscal year, a pit-structure and buried pottery features from the Middle to Final Jōmon periods were investigated.

The pit structure had a complex fireplace, seen in many structures from the end of the Middle Jōmon, containing multiple hearths. Also, as many as 25 storage pits, used for keeping nuts, of the Final Jōmon were found, from which acorns were recovered in bulk. More than 30 buried jar features, thought to have been burials of infants, were distributed over an area 15 m east–west by 10 m north–south, and from one of these a portion of a skull thought to be that of an infant was recovered.

From the water course which accompanied a spring, a large amount of pottery and stone tools mainly from the latter portion of the Middle Jōmon period, together with various wooden implements such as an axe handle, a bow, and fire-starting gear were recovered. Baskets and mats woven from tree bark were in abundance, and the shells of nuts such as walnuts, acorns, chestnuts, horse chestnuts, as well as animal bones were found. These materials are a source of data essential for deciphering the contents of the livelihood of the time. Also, lacquer-painted vessels and ornaments were recovered in great numbers, and as materials related to lacquer for the Middle Jōmon period have previously been scarce for the Tōhoku region, the results of this investigation are drawing attention.


A waterside work area, rare for the Kinki region

At the Minushi Jinja Higashi Site in Jōyō City, Kyoto Prefecture, excavations have been carried out since the 2017 fiscal year. In the investigations of fiscal 2019, from the remains of a water course a feature consisting of a wooden frame made for utilizing the water’s edge, together with a wooden path and lines of stakes from the Final Jōmon period (approximately 3,000 years ago), were discovered.

The wooden frame feature was 2.3 m in overall length, 0.7 m wide, with whole and split logs laid down as joists, and after spanning these with horizontal members, several stakes were driven at the short end to make the frame fast. The wooden path was made by spreading split logs over an area 3.5 m long by 0.4 m wide, and is thought to have been used to provide convenient access to the frame feature. In addition, an area stretching at least 4.2 m of wooden members and stakes standing in line was found in the center of the water course.

These features were all built parallel to the direction of the water course, and it is surmised that tasks utilizing the flowing water for processing food and wooden materials were conducted. In the environs, the Moriyama Site where a group of Late Jōmon pit-structures has been detected is situated on a hilltop, and the Shimo Mizushi Site and Kohijiri Site of the Late to Final Jōmon periods extend over the lowland area. Similar features have been found centered in eastern Japan thus far in large numbers, but in recent years they have also been found in succession in the Kinki region as well, raising issues for the reevaluation of the image of Jōmon settlements for western Japan.


Wooden frame feature at the Minushi Jinja Higashi Site (photo courtesy of the Kyoto Prefecture Research Center for Archaeological Properties)


Panoramic view of the Early Yayoi period rice paddy at the Nakanishi Site (photo courtesy of the Archaeological Institute of Kashihara, Nara Prefecture)

Yayoi Period  (Kawahata Jun)

Yayoi inkstones, one after another

Introduced in this summary for 2019, further information on Yayoi period inkstones has been coming in. Were people of the Yayoi period fully able to use writing? The existence of inkstones could be material proof determining an issue as big as this. This time, the “discovery” of inkstones and whetstones (tools for grinding charcoal) was at the large-scale Yayoi period settlement representative of Japan, the Special Historic Site of Yoshinogari in Kanzaki City and Yoshinogari Town, Saga Prefecture. Discovered in the process of carefully examining and sorting previously recovered finds, this raises the possibility that writing was used in the Ariaki Sea coastal region in the Yayoi period. In addition to this, such “discoveries” of items that were possibly inkstones have been made one after another in various regions through reexaminations of recovered artifacts, and Yayoi period research is currently being roiled by an unprecedented boom in inkstones.


The primeval Japanese landscape?

At the Nakanishi Site in Gose City, Nara Prefecture, scenery of extensive rice paddy maintained by people of the Yayoi period has come to light. Taken together with what has been discovered previously, rice paddy extending 43,000 m2 in area has been found, and as an example uncovered for the Early Yayoi period (approximately 2,500–2,400 years ago) when wet-rice agriculture had only recently been transmitted to Japan, it boasts the top level in terms of area nationwide. The fields were minutely sectioned off with small ridges about 30 cm in width, and skillfully utilizing the sloping topography, they are thought to have been devised so that water would overflow the ridges to spread over a wide area. Footprints left by Yayoi people in the muddy rice fields clearly survived, providing a glimpse of the primeval Japanese landscape filled with people diligently engaged in farm work.


Side-by-side moated settlements come to light

The Tawayama Historic Site of Matsue City, Shimane Prefecture, is a moated settlement made at the eastern end of Lake Shinji, with fences and three concentric moats encircling a hilltop, and a residential district unfolding on the outside. At a location just 500 m to the northern side of the Tawayama Site, the existence of a moated settlement known as the Jigode Site is newly coming to light. Based on excavations a moat with a Y-shaped cross section has been found, and within the area enclosed by it pit structures have been discovered. The difference in nature from the Tawayama Site, characterized by the lack of a residential district within the moats, is thus becoming clear. Both settlements are known to have existed simultaneously during the Early Yayoi period, so the relationship between these two moated settlements standing side-by-side is gathering attention.


Kofun Period  (Fujii Kōji)

New discoveries about the nature of the Final Kofun

Investigations of Final Kofun period tombs were conducted in Yamato, which may be called the center of Kofun culture, and discoveries made which raise hopes for future advances in research.

The Koyamada Tomb is a large-scale 70-m square mound built in the middle portion of the seventh century, discovered in 2014 in Asuka Village, Nara Prefecture, and it is known that the northern face of the mound was made with piled stone slabs. In the investigation of the 2018 fiscal year, it became clear that the southern edge extends to 80 m in size, and the western face of the mound was also made with piled stone slabs. Additionally, conditions of utilization following the construction of the tomb became known, as not long after it was built the stone slabs on the western face were removed and a jar burial was made on top of the mound.

Historic Site Hirano Tsukaanayama Kofun in Kashiba City, Nara Prefecture, is a square mound of more than 20 m on each side, built in the latter half of the seventh century, having a compartment-style stone chamber with a side entrance. In recent excavations it was discovered that the sloping faces of the mound had been paved with stones of volcanic tuff produced at Mount Nijō, and that the stones used for the compartment-style chamber had holes to receive levers (used for moving the stones). As this type of stone paving is mainly seen in royal-class tombs, the discovery is valuable for considering the identity of the occupant of Hirano Tsukaanayama Kofun.


From Early period settlements to chiefly residences

The Kobe Site in Usa City, Ōita Prefecture, is a settlement with a surrounding moat roughly 120 m north–south by 100 m or greater east–west,  having projections at two locations. In an excavation conducted by the Usa City Board of Education in 2019, it was learned that a rectangular precinct was made within this moated settlement, which was established at the start of the Early Kofun period, and subsequently a large-scale embedded-pillar building was erected within the precinct. This has also drawn attention because the time when the large-scale embedded-pillar building was made coincided with the Akatsuka tomb of Historic Site Kawabe-Takamori Kofun Group located in close proximity. In addition to providing valuable knowledge about the process of emergence of chiefly residences from Early Kofun period settlements, the Kobe Site discovery is important for knowing about the reception of Kofun culture in northern Kyushu.


Contact between Epi-Jōmon and Kofun cultures

In the northern Tōhoku region and Hokkaido during the Kofun period, rather than the Kofun culture represented by keyhole mounds, the Epi-Jōmon  culture was unfolding, which like the Jōmon was based on a livelihood of fishing and hunting. At the Inohana (1) Site in Shichinohe Town, Aomori Prefecture, six pit burials of the fourth century which parallel the Early Kofun period were discovered. Four of these had posthole-shaped pits characteristic of Epi-Jōmon culture pit burials, and in addition to Epi-Jōmon pottery, Haji ware, iron knives, glass beads and so forth were recovered, whereas by contrast the remaining two pit burials lacked the posthole-shaped features, and yielded Haji ware and various types of beads including cylindrical beads of jasper and green tuff, and round amber beads. This can be called a situation in which elements of Epi-Jōmon culture such as the pottery and posthole-shaped pits coexisted with elements of Kofun culture such as Haji ware and beads. This indicates there was exchange between the peoples of the Epi-Jōmon and Kofun cultures. We probably need to pay more attention to this cultural variety which was also nurtured within the archipelago of the Kofun period.

ncient Period  (Morisaki Kazuki)

An undiscovered Ancient government office?

Features thought to be facilities related to an Ancient government office complex have been discovered at the Wakamiya no Higashi Site in Nankoku City, Kōchi Prefecture. This site has been investigated for multiple years by both the Nankoku City Board of Education and the Kōchi Prefecture Archaeological Center. As a result, it has become clear that during the Ancient period there were large-scale embedded-pillar buildings and partitioning fences, and buildings with regularly placed internal pillars thought to represent a group of storehouses, standing within the area of the site. The large-scale buildings are regarded as having been erected in the latter half of the seventh century, with the postholes being 1 m or more on a side, holding pillars that were about 30 cm in diameter, with a large between-pillar span of 3 m, the largest structures within Kōchi Prefecture. They are regarded as high-class buildings comprising a district government office, the administrative unit of the day, in which case the storehouse group would have been the official granary for tax revenues. A rectangular plaque decoration (junpō) for the type of belt worn by government officials of the Ancient period was recovered in the 2019 fiscal year investigation, supporting the possibility that the group of buildings was a facility related to a government office.


Successive discoveries in the environs of capitals

In recent years, new discoveries have come one after another in the environs of Ancient period capitals. In Kyoto there is the famous Tōji temple which has been transmitting the light of Buddhism from the Heian period to the present day, and at the Historic Site of Saiji, the location of Saiji temple built at the same time as Tōji, a feature regarded as the podium of a five-storied pagoda has been found. It is believed to retain its form from the time of the temple’s founding, and is understood to have boasted the grandest scale for a building within the Heian capital district. This tells us that formerly there were two five-storied pagodas standing side-by-side at the front entrance to the Heian capital.

At the Historic Site of Miyataki in Yoshino Town, Nara Prefecture, results have also come from an excavation with ties to Ancient period Emperors. This site has been known since the Meiji period, and the possibility that it was the detached palace, Yoshino no Miya, seen in the Nihon shoki and Shoku Nihongi chronicles has been pointed out. This time, in an excavation by the Archaeological Institute of Kashihara and Yoshino Town, the appearance of a well-ordered arrangement of large-scale embedded-pillar buildings has become clear, backing up the previously held detached palace theory.

A new discovery of great interest has been made at the Fujiwara Palace Special Historic Site in Kashihara City, Nara Prefecture. The precinct enclosing the Imperial Audience Hall, the stage for ceremonies and political affairs centering on the Emperor, is called the Imperial Audience Hall compound. Until now the Imperial Audience Hall compound at the Fujiwara Palace was thought to contain no buildings other than the Imperial Audience Hall, but it has newly become clear that there was an internal cloister (a compound corridor standing on foundation stones) enclosing the northern side of that building. The details of this cloister closely resemble the Former Naniwa Palace in Osaka City, which is similar to the Fujiwara Palace in its scale and composition. This discovery can be called a significant result for knowing the relationship between these two centers, as well as the transition in structure of ancient palaces over time.


A stone wall makes an appearance after 400 years at the Special Historic Site, Kumamoto Castle


Medieval/Early Modern Periods  (Ōmi Toshihide)

Interest in Medieval and Early Modern castles

In recent years investigations have become particularly active for Medieval and Early Modern castles and residences. In the 2019 fiscal year as well, excavations were carried out one after another throughout the country on castle remains for the purpose of preservation and utilization. Among these, while there were castles that are well known nationwide such as Sunpu Castle and Special Historic Site Himeji Castle on the one hand, there were in fact a great many castles that came under archaeological investigation, from those of daimyo of the Sengoku period and continuing under the bakuhan system, to Medieval fortresses. As a result, there were new historical clarifications that emerged with regard to each castle and region, and concerning Japanese history overall as well.


New discoveries bred by disasters

In recent years, major disasters have been assaulting the Japanese archipelago in nearly annual fashion. These disasters also cause great damage to precious cultural properties, but unexpected discoveries may be encountered during recovery as well. At the Special Historic Site of Kumamoto Castle where restoration work is underway for the five-storied turret of the Iida bailey, a portion of stone wall from the time of the castle’s construction by Katō Kiyomasa was found. In the 2016 Kumamoto earthquakes, a single column of stone wall holding up the reconstructed turret drew attention, but with the dismantling of the stone wall in conjunction with restoration work an older stone wall 8.5 m to the inside was revealed. This older stone wall had been buried around 1615 when the stone work forming the foundation of the turret was expanded, thus making an appearance for the first time in 400 years. Thanks to an excavation conducted under extreme circumstances in terms of schedule and technical difficulty, one bit of the history of Kumamoto Castle has come to light.


Discovery of a stone wall through dismantling and repair

In Nakagusuku Village, Okinawa Prefecture, the dismantling and repair of the stone walls of Historic Site Nakagusuku Castle has been underway since the 2016 fiscal year. On the occasion of this repair, some of the stone wall from the initial construction of the castle has been discovered within the modern castle walls (latter half, nineteenth–first half, twentieth centuries). From the recovered glazed ceramics this stone wall is thought to date from the first half of the fourteenth century, so the date of castle construction, which until now had been regarded based on documentary and other evidence as belonging to the latter half of the fourteenth century, has been put back a half century in a single stroke. The stone wall that for a long period had not received sunlight was whitish compared with the surrounding material, and also smaller in scale, but the manner in which the finely processed dressed stone was carefully piled up is an extremely important finding for knowing the origins and initial technology of gusuku (castle) building, as well as the transitions of gusuku over time.